Synthesis, structural investigation and thermal analyses of a novel coordination compound [Cd(DAT)₆](HTNR)₂·3.5H₂O (DAT = 1,5-diaminotetrazole, H₂TNR = styphnic acid)

A novel coordination compound [Cd(DAT)₆](HTNR)₂·3.5H₂O has been synthesized by using 1,5-diaminotetrazole (DAT) as ligand and characterized by applying X-ray single crystal diffraction, elemental analysis and FT-IR spectroscopy. The central cadmium (II) cation is coordinated by six N atoms of six DAT ligand molecules to form a six-coordinated and slightly distorted octahedral structure. With the extensive intermolecular hydrogen bonds, molecular units of [Cd(DAT)₆](HTNR)₂·3.5H₂O are linked together to form a 3D net structure with pore canals. Mulliken charge distribution of DAT in bulk state has been obtained from the density functional theory (DFT) with the B3LYP method employing the 6-31G^** basis sets to interpret the reason why the coordination site of DAT is N(4) atom of the tetrazole ring. Thermal decomposition mechanism of the title compound was predicted based on DSC, TG-DTG and FT-IR analyses results. The kinetic parameters of the first exothermic process of the title compound were studied by applying the Kissinger's and Ozawa-Doyle's methods.